Steam boiler



July 18, 1933.

H. JEZLER STEAM BOILER Filed Feb. 27, 1931 Patented July 18, 1933 1 N TED STATES HUBERT ,JEZLER, or zonion, swrrzERLann Application filed February 273 1931, Serial No'. 518,760, and. ,in 'switzerland March ,5, 1930.

The present invention relates to a steam boiler in particular a high pressure boiler.

The main object of my invention is to improve the thermal efficiency of steam gener- V ating plants generally and to provide a boil-' er which generates steam most economically.

l attain these and other objects by a boiler comprising a primary part in which'water 'is heated near to its boiling point, care being taken that no considerable evaporation takes place, and a secondary part in which evaporation of the highly preheated water takes place and in which the steam may be superheated.

According to theinvention a throttle and regulating device is arranged between the primary and the secondary parts, and a reg- ;ulating device for the boiler feed which, preferaby at the same time, serves the purpose of a safety valve.

In the primary part, the pressure and temperature of the water is held within such limits that here no appreciable evaporation is possible this part of the boiler, therefore, remains filled with water at a high temperatureduring the working. This water flows through a throttle device into the secondary part of the boiler where it is first transformed into steam, which is superheated afterwards.

In the attached drawing, an example of a boiler according to the invention is shown diagrammatically in axial section.

The boiler shown comprises a primary part 1 with the furnace and the secondary part 2, which two parts are connected with ,each other by pipes 13,14 and 16and a valve 3. The valve 3 comprises a casing 21 in which a piston is slidably mounted. A coiled spring 22, pressingthe valve body23 on its seat, tends toclose thecommunication between the parts 1 i and 2. Combustion takes place principally in the combustion chamber 7, from whichtheiheating gasesare drawn through tubes 8 and flow consecutive ly through tubes of the evaporator 2 and to the preheater 6.

The feed water is supplied through a pipe 9 into the cylinder 25 of the device 4, governing the feeding. A piston 10 of the device 4 isprovided with an annular groove 26 which, in the position shown in the'drawing,

opens the water 'inlet for the feed water pump 5. By means of the pump 5, the water islfo'rced through the pipe 11 to the preheater 6. The rate of flow of the feed water in the preheater 6 is kept low. The heated water leaves the preheater 6 through the pipe 12, and passes into the primary boiler 1. After it has passed over the heating surfaces of this, and has be'en further heated, it flows through the connecting pipes 13,14,

The valve 3 iskept closed by spring 22 actin on valve spindle '15. On the opening of the throttle valve 3, the highly heated water flows through the pipe 14: into the evaporator and risuperheater 2. The superheated steam formed in part 2 finally reaches the engine through the pi e '17, part of the steam flows through the feedwater pump 5.

The feed water'regulation takes place as follows: i 1 I I On :the piston 10 of the device 4 acts a spring 27, said-1piston10 is moreover infiuj enced by :the boilerrpressure by means ofthe connecting pipe 19. If the boiler pressure rises pistonlO is forced upwards against the action of spring27 until ,the feed water pipe 9 is closed. Should the boiler pressure rise 50 still further,then the piston 10 is forced up higher, so that the outlet 20 is opened with an immediate fall of pressure in the boiler 6. When the piston 10 returns a reversalof the flow of fluid in thepipe 19 takes place,the 485 feed water inlet is opened by the groove26 in the. piston 10, and the water passesagain to the feed water pump 5 andfrom the pump 5 intojthe preheater 6.

In the present example, a continuously run- 3 ning feed pump 5 is provided, the water inlet of which is controlled' -by the device 4. A i Y device 4 may, however, be used controlling the steam supply to the feed pump so that .the pump works only :during periods of supply.

The hrottling device 3.is contrived as follows V The inner diameter of the pipe or nozzle 14 is made so that 1n no case more water can ranch 18 to the 7 flow through than can be evaporated and superheated in the secondary part 2. By means of the valve body 15, 23 which is under spring pressure and which may be operated in anysuitable manner, for example by a speed governor,the quantity of steam is exactly suited to the consumption. The pressure acting on valve spindle 15 is higher than the pressure acting on the piston 10 of the device 4, consequently. an increase in steam pressure in the boiler to 'a predetermined extent, will move the piston 10, but not the valve spindle 15. It is understood that the throttling and regulating device 3 is only conventionallv illustrated, and in practice 'may have various details or features employed in a modern speed governor.

The advantages of the boiler according to the invention, inparticular of a high pressure boiler, as compared with others, are much as follows A boiler which remains constantly filled with Water requires little attention. The feeding of such a boiler-is extremely simple, since it can be effected with certainty and entirely automatically by means of a suitable device. The regulating device can also serve as an overflow, in which case a separate safety valve is unnecessary. As the position of the pistons used in the regulating. device corresponds to the working condition at the mo- -ment, the use of level indicators or water gauges is not necessary.

In the primary part'no steam is generated or only a very small production of steam takes place, and the boiler water is only'subjected'to heating and to a slight circulation and not to ebullition.

A further advantage of the boiler according to the invention is that in working it for example with coal-dust or oil firing, the con- "struction of expensive boiler drums is not necessary.

Vhat I wish to claim and secure by U. S. Letters Patent, is l i 1. In a steam generating plant, a feed water preheater, a'pump for delivering feed Water thereto, a valve for controlling the intake to said pump, achamber connected to said preheater, and a piston in saidchamber and operated by the pressure of the water in saidchamber, and operatively connected to said valve to close the latter when said pressure exceeds a predetermined limit, said chamber havingan outlet controlled by said piston to permit escape of water from said preheater when the pressure exceeds a predetermined limit. I

" 2. In a steam, generating plant, a water heater, a valve casing, a reciprocating memher in said casing, a connection between said chamber and said water heater for pernnttlng delivery of water from said heater to said 7 said casing and the inlet'of said pump, said connections being closed by said member when the. pressure in said heater exceeds a predetermined limit, and said casing having an outlet also controlled by said member for permitting escape of liquid from said heater When the pressure inthe latter exceeds a predetermined limit. r

3 In a steam generating plant, a water heater, a pump for delivering water thereto, a valve for controlling the intake to said pump, a piston foroperating said valve to close the latter when the pressure in said heater exceeds a predetermined limit, a cylinder inclosing said piston, connections between said pistonand said water heater, and an outlet permitting escape of water from said water heater, said outlet being controlled by said piston.

I. In a steam generating plant, the combination of a heating unitfor water, a feed pump for. delivering water to said unit, and valve mechanism automatically operated in accordance with the pressure of the water in said unit and having means for controlling the flow of water to said pump, and means for relieving the pressure in said unit when the pressure therein exceeds a predetermined -evaporator and superheater, a feed pump for delivering Water to said'primary chamber to maintain the latter *completely' filled with water, an outlet fromthe top of said primary chamber to said secondary chamber and having a throttle valve,'and a spring tending to close said valve against the pressure in said primary chamber, said valve being mechanically operable to permit delivery of water to 'saidsecondary chamber at a rate depending upon the'steam consumption.

"HUBERT JEZLER. 

